[pbs-devel] [PATCH proxmox-backup v4 2/3] expose the unpriviliged total in the api and use it in the GUI

[Daniel Tschlatscher <d.tschlatscher@proxmox.com>]

Until now, the total size for a datastore was reported as the total
space on the filesystem. On ext4 filesystems this number will not
match the observed behaviour when some amount of blocks are reserved
though, as the proxmox-backup-proxy uses the unpriviliged 'backup'
user. Therefore backup-ing new data would fail, even though the GUI
still displays that X% of the datastore is free.
I think using the unpriviliged total makes more sense as it
communicates to the user how much they can actually still store on the
datastore, rather than the full total of which some part might not be
usable.

This will also not lead to issues in the GUI when the reserved space
is written to, because the value reported by statfs will automatically
increase accordingly.
I.e. when the unprivliged space is full and a 500MB file is written by
the root user, the fields for "unpriv_total" and "used" will both
increase by this amount, simply keeping the usage at 100%.

Note: I've opted to create a new field in the API result for the
unpriviliged total of the datastore, as overwriting the existing total
might break compatibility for users who retrieve the actual datastore
disk size this way.

Signed-off-by: Daniel Tschlatscher <d.tschlatscher@proxmox.com>
---
No changes from v3

 pbs-api-types/src/datastore.rs        | 5 +++++
 src/api2/admin/datastore.rs           | 3 +++
 src/api2/status.rs                    | 1 +
 www/dashboard/DataStoreStatistics.js  | 6 +++---
 www/datastore/DataStoreListSummary.js | 4 ++--
 5 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/pbs-api-types/src/datastore.rs b/pbs-api-types/src/datastore.rs
index 0af11b33..d1730715 100644
--- a/pbs-api-types/src/datastore.rs
+++ b/pbs-api-types/src/datastore.rs
@@ -1235,6 +1235,8 @@ pub struct GarbageCollectionStatus {
 pub struct DataStoreStatus {
     /// Total space (bytes).
     pub total: u64,
+    /// Total space available to unpriviliged users (bytes)
+    pub unpriv_total: u64,
     /// Used space (bytes).
     pub used: u64,
     /// Available space (bytes).
@@ -1269,6 +1271,8 @@ pub struct DataStoreStatusListItem {
     pub store: String,
     /// The Size of the underlying storage in bytes. (-1 on error)
     pub total: i64,
+    /// The total space available to unpriviliged users (-1 on error)
+    pub unpriv_total: i64,
     /// The used bytes of the underlying storage. (-1 on error)
     pub used: i64,
     /// The available bytes of the underlying storage. (-1 on error)
@@ -1301,6 +1305,7 @@ impl DataStoreStatusListItem {
         DataStoreStatusListItem {
             store: store.to_owned(),
             total: -1,
+            unpriv_total: -1,
             used: -1,
             avail: -1,
             history: None,
diff --git a/src/api2/admin/datastore.rs b/src/api2/admin/datastore.rs
index 7b103fb7..cd5d01e8 100644
--- a/src/api2/admin/datastore.rs
+++ b/src/api2/admin/datastore.rs
@@ -715,12 +715,14 @@ pub async fn status(
             total: storage.total,
             used: storage.used,
             avail: storage.available,
+            unpriv_total: storage.used + storage.available,
             gc_status,
             counts,
         }
     } else {
         DataStoreStatus {
             total: 0,
+            unpriv_total: 0,
             used: 0,
             avail: 0,
             gc_status,
@@ -1804,6 +1806,7 @@ pub fn get_rrd_stats(
 
     let mut rrd_fields = vec![
         "total",
+        "unpriv_total",
         "used",
         "read_ios",
         "read_bytes",
diff --git a/src/api2/status.rs b/src/api2/status.rs
index b918156e..26ca750c 100644
--- a/src/api2/status.rs
+++ b/src/api2/status.rs
@@ -69,6 +69,7 @@ pub async fn datastore_status(
         let mut entry = DataStoreStatusListItem {
             store: store.clone(),
             total: status.total as i64,
+            unpriv_total: (status.used + status.available) as i64,
             used: status.used as i64,
             avail: status.available as i64,
             history: None,
diff --git a/www/dashboard/DataStoreStatistics.js b/www/dashboard/DataStoreStatistics.js
index 38f7a2fe..8dbd1caf 100644
--- a/www/dashboard/DataStoreStatistics.js
+++ b/www/dashboard/DataStoreStatistics.js
@@ -3,7 +3,7 @@ Ext.define('pbs-datastore-statistics', {
 
     fields: [
 	'store',
-	'total',
+	'unpriv_total',
 	'used',
 	'avail',
 	'estimated-full-date',
@@ -27,7 +27,7 @@ Ext.define('pbs-datastore-statistics', {
 	    name: 'usage',
 	    calculate: function(data) {
 		let used = data.used || 0;
-		let total = data.total || 0;
+		let total = data["unpriv-total"] || 0;
 		if (total > 0) {
 		    return used/total;
 		} else {
@@ -78,7 +78,7 @@ Ext.define('PBS.DatastoreStatistics', {
 	},
 	{
 	    text: gettext('Size'),
-	    dataIndex: 'total',
+	    dataIndex: 'unpriv-total',
 	    sortable: true,
 	    width: 90,
 	    renderer: v => v === undefined || v < 0 ? '-' : Proxmox.Utils.format_size(v, true),
diff --git a/www/datastore/DataStoreListSummary.js b/www/datastore/DataStoreListSummary.js
index c7b67d56..3714528e 100644
--- a/www/datastore/DataStoreListSummary.js
+++ b/www/datastore/DataStoreListSummary.js
@@ -52,10 +52,10 @@ Ext.define('PBS.datastore.DataStoreListSummary', {
 	    vm.set('maintenance', '');
 	}
 
-	let usage = statusData.used/statusData.total;
+	let usage = statusData.used/statusData["unpriv-total"];
 	let usagetext = Ext.String.format(gettext('{0} of {1}'),
 	    Proxmox.Utils.format_size(statusData.used, true),
-	    Proxmox.Utils.format_size(statusData.total, true),
+	    Proxmox.Utils.format_size(statusData["unpriv-total"], true),
 	);
 
 	let usagePanel = me.lookup('usage');
-- 
2.30.2